Member Avatar for dorien

I am trying to run an easy Android ndk app in cpp, but I get UnsatisfiedLink Error for the Generate() function.

Any help would be appreciated. I am quite fluent in c++, but my java is a little bit rusty. I have been trying a lot of tips from the web concerning naming, but so far no luck. Here are my files:

native.cpp:

#include <string.h>
#include <jni.h>

jstring Java_com_optimuse_app_OptimuseAppActivity_generate(JNIEnv* env, jobject thiz){
    return env->NewStringUTF("Hello from JNI !");
}

Android.mk:

LOCAL_PATH := $(call my-dir)

include $(CLEAR_VARS)

LOCAL_MODULE    := native
LOCAL_SRC_FILES := native.cpp

include $(BUILD_SHARED_LIBRARY)

I compile this with ndk-build and all goes well, it provides me with a libnative.so, that is located in the project directory. I use eclipse for the rest.

OptimuseAppActivity.java:

package com.optimuse.app;
import android.app.Activity;
import android.widget.TextView;
import android.os.Bundle;

public class OptimuseAppActivity extends Activity 
{
    @Override
    public void onCreate(Bundle savedInstanceState)
    {
        super.onCreate(savedInstanceState);
        TextView  tv = new TextView(this);
        tv.setText( generate() );
        setContentView(tv);
    }

    public native String generate();

    static {
        System.loadLibrary("native");
    }
}

And the automatically generated AndroidManifest.xml

<?xml version="1.0" encoding="utf-8"?>
<manifest xmlns:android="http://schemas.android.com/apk/res/android"
    package="com.optimuse.app"
    android:versionCode="1"
    android:versionName="1.0" >

    <uses-sdk android:minSdkVersion="15" />

    <application
        android:icon="@drawable/ic_launcher"
        android:label="@string/app_name" android:hasCode="true">
        <activity
            android:name="com.optimuse.app.OptimuseAppActivity"
            android:label="@string/app_name" >
            <intent-filter>
                <action android:name="android.intent.action.MAIN" />

                <category android:name="android.intent.category.LAUNCHER" />
            </intent-filter>
        </activity>
    </application>

</manifest>

Thank you for any suggestions, been searching for a few hours now!

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Member Avatar for dorien

The cpp syntax was a bit different from the c you see everywhere...

extern "C" {
JNIEXPORT jstring JNICALL Java_com_optimuse_app_OptimuseAppActivity_generate(JNIEnv* env, jobject thiz){
    return env->NewStringUTF("Hello from JNI cpp!");
}}
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